28057984 has 64 divisors (see below), whose sum is σ = 59976000. Its totient is φ = 13036032.

The previous prime is 28057979. The next prime is 28058021. The reversal of 28057984 is 48975082.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×28057984² = 1574500932288512, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28057984.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201787 + ... + 201925.

It is an arithmetic number, because the mean of its divisors is an integer number (937125).

Almost surely, 2^28057984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28057984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29988000).

28057984 is an abundant number, since it is smaller than the sum of its proper divisors (31918016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28057984 is a wasteful number, since it uses less digits than its factorization.

28057984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255 (or 243 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 28057984 is about 5296.9787615206. The cubic root of 28057984 is about 303.8683640608.

The spelling of 28057984 in words is "twenty-eight million, fifty-seven thousand, nine hundred eighty-four".